AMOEBINA 











Fig. 142. a, Pelomyxa palustris, Xl30 (Kiihn); b, P. villosa, X420 

 (Leidy); c, Vahlkampfia Umax, XS30 (Kudo); d, V. patuxent, X830 

 (Hogue); e, f, Hartmamiella hyalina, X1170 (Dobell); g, h, H. castel- 

 lanii, X1590 (Hewitt). 



bacteria; multiplication by fission or budding; encystment rare; 

 cysts uninucleate. 



Genus Hartmannella Alexeieff. Small amoebae with the follow- 

 ing nuclear characteristics: vesicular; large endosome central and 

 chromatin granules scattered along the periphery; at the time of 

 division endosome disintegrates and chromosomes and spindle 

 fibers appear; there are no so-called polar caps during division as 

 are found in Vahlkampfia, from which differentiation is difficult. 



H. hyalina (Dangeard) (Fig. 142, e, f). Body more or less 

 rounded; less than 20/i in diameter; a contractile vacuole; binary 

 fission; spherical cyst, 10-15/x in diameter, covered with a smooth 

 inner and a much wrinkled outer wall ; easily cultivated from old 

 faeces of man and animals; also in soil and fresh water. 



H. castellanii Douglas (Fig. 142, g, h). In association with fungi 



